Solar Basics- Energy from the Sun

The sun has produced energy for billions of years. Solar energy is the sun’s rays (solar radiation) that reach the Earth. This energy can be converted into other forms of energy, such as heat and electricity.


Solar Energy Can Be Used for Heat and Electricity When converted to thermal (or heat) energy, solar energy can be used to:

Heat water — for use in homes, buildings, or swimming pools

Heat spaces — inside homes, greenhouses, and other buildings

Heat fluids — to high temperatures to operate a turbine to generate electricity


Solar energy can be converted to electricity in two ways:


• Photovoltaic (PV devices) or “solar cells” change sunlight directly into electricity. Individual PV cells are grouped into panels and arrays of panels that can be used in a wide range of applications ranging from single small cells that charge calculator and watch batteries, to systems that power single homes, to large power plants covering many acres.
• Solar Thermal/Electric Power Plants generate electricity by concentrating solar energy to heat a fluid and produce steam that is used to power a generator. In 2010, solar thermal-power generating units were the main source of electricity at 13 power plants in the United States.